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The first crystal structure of an archaeal helical repeat protein.

ABSTRACT: The crystal structure of ST1625p, a protein encoded by a hypothetical open reading frame ST1625 in the genome of the hyperthermophilic archaeon Sulfolobus tokodaii, was determined at 2.2 A resolution. The only sequence similarity exhibited by the amino-acid sequence of ST1625p was a 33% identity with the sequence of SSO0983p from S. solfataricus. The 19 kDa monomeric protein was observed to consist of a right-handed superhelix assembled from a tandem repeat of ten alpha-helices. A structural homology search using the DALI and MATRAS algorithms indicates that this protein can be classified as a helical repeat protein.

SUBMITTER: Yoneda K

PROVIDER: S-EPMC1952456 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature

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The first crystal structure of an archaeal helical repeat protein.

Yoneda Kazunari K Sakuraba Haruhiko H Tsuge Hideaki H Katunuma Nobuhiko N Kuramitsu Seiki S Kawabata Takeshi T Ohshima Toshihisa T

Acta crystallographica. Section F, Structural biology and crystallization communications 20050630 Pt 7

The crystal structure of ST1625p, a protein encoded by a hypothetical open reading frame ST1625 in the genome of the hyperthermophilic archaeon Sulfolobus tokodaii, was determined at 2.2 A resolution. The only sequence similarity exhibited by the amino-acid sequence of ST1625p was a 33% identity with the sequence of SSO0983p from S. solfataricus. The 19 kDa monomeric protein was observed to consist of a right-handed superhelix assembled from a tandem repeat of ten alpha-helices. A structural hom ...[more]

PMID: 16511116

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